Quiver

2023 Specialized Demo Expert vs 2023 Trek Session C 27.5 Frameset

The Trek Session C 27.5 Frameset size closest to your S3 is the L. Compare the L instead

What changes on the Trek Session C 27.5 Frameset

Compared with the Specialized Demo Expert in S3, the Trek Session C 27.5 Frameset in S places the top of the head tube 16 mm lower and 36 mm further back, relative to the bottom bracket. Its wheelbase is 43 mm shorter, which can contribute to quicker direction changes.

Frame stack
−16 mm
Lower front end
Frame reach
−36 mm
Shorter frame reach
Wheelbase
−43 mm
Shorter: quicker to change direction
Head angle
+0.7°
Steeper: sharper steering
Chainstays
−3 mm
Shorter: livelier

The two frames

2023 Specialized Demo Expert (S3)The Specialized Demo Expert frame drawn to scale.J 1259

Only the Specialized Demo Expert is drawn. The Trek Session C 27.5 Frameset numbers we have for size S are missing the seat angle.

Geometry side by side

MeasurementSpecialized Demo Expert S3Trek Session C 27.5 Frameset SDifference
Reach446mm410−36 mm
Stack632mm616−16 mm
Head tube angle62.8°63.5°+0.7°
Seat tube angle76.8°not listed
Chainstay length448mm445−3 mm
Wheelbase1259mm1216−43 mm
Seat tube length420mm425+5 mm
Head tube length105mm115+10 mm
Effective top tubenot listed579
BB dropnot listed20
BB heightnot listed356
Standovernot listed738

Differences are the Trek Session C 27.5 Frameset minus the Specialized Demo Expert. Full charts: 2023 Specialized Demo Expert, 2023 Trek Session C 27.5 Frameset.

Where each sits in its class

Specialized Demo ExpertTrek Session C 27.5 Frameset

AggressivePositionUpright
CalmSteeringQuick
PlayfulBalancePlanted

Each bike is ranked against the other downhill bikes on Quiver, on frame geometry alone. Not your hand position or ride feel.

What each ships with

The stock build of each bike's first listed trim. Parts that match are dimmed.

PartSpecialized Demo ExpertExpertTrek Session C 27.5 Frameset27.5 Frameset
ForkRockShox BoXXer 29not listed
Rear shockRockShox Super Deluxe Selectnot listed
ShifterSRAM GX DHnot listed
DerailleurSRAM GX DHnot listed
CassetteSRAM GX DHnot listed
ChainSRAM PC1110not listed
CranksetSpecialized DESCENDANT DHnot listed
Bottom bracketSRAM DUBnot listed
TireSpecialized Butchernot listed
BrakeSRAM Code RSnot listed
StemSpecialized Descendantnot listed
SaddleSpecialized Henge DHnot listed
Framenot listedTrek OCLV
Headsetnot listedFSA Orbit

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